Vehicular mobile device alarm sensor

摘要

The presence of an RF signal in an expected location emanating from a mobile device within the expected location is detected by first antenna positioned in the expected location. False alarm discrimination is achieved by the square ratio of the operator's cellphone signal close to the antenna(s) versus the blocked external signals from much greater distance. A comparator compares the RF signal emanating from the mobile device in the expected location with a threshold signal and determines whether the mobile device is operating, and, if so, an alarm responsive to the comparator is triggered.

主权项

1. A system operable to detect a presence of an RF signal emanating from a mobile device in an expected location, the system comprising:
a first antenna positioned in the expected location operable to detect the RF signal emanating from the mobile device in the expected location; a comparator operable to compare the RF signal emanating from the mobile device in the expected location with a threshold signal and determining whether the mobile device is operating; and an alarm responsive to the comparator operable to alert to an operation of the mobile device, wherein the threshold signal is dynamically adjusted by sampling RF signals emanating from outside the expected location and comparing the RF signals to a value for the RF signal emanating from the mobile device in the expected location.